A conference data presentation indicated that in a survey of allergy rhinitis sufferers, 51% of patients blamed pollution for their worsening symptoms, while 80% incriminated climate change. Associate Professor Jonny Peter, head of the division of Allergy and Clinical Immunology at the University of Cape Town said there is some evidence of significantly stronger allergenicity in pollen from trees growing at increased temperatures and that climate change may affect air pollutant levels, such as tropospheric ozone (O₃), but a lot more research is needed, before firm conclusions can be made.
Another recent survey conducted among 1 184 doctors who belong to the American Academy of Allergy Asthma and Immunology (AAAAI) confirmed that most doctors are witnessing medical problems caused by climate change among their patients. Nearly two-thirds reported a need for increased care for allergic sensitisation and symptoms following exposure to plants or mould.
Possible effects of climate change on respiratory allergy could be as follows:
- An increase in rain and heavy downpours, such as thunderstorms could lead to asthma epidemics, with sudden pollen surges and ruptures. Last year, tragedy struck Melbourne following the death of nine asthma sufferers after an unprecedented thunderstorm. The moisture in the air caused pollen to burst into hundreds of allergenic particles – akin to 150 bombs exploding at the same time, which triggered widespread asthma attacks.
- Global warming could increase the length and intensity of the pollen season causing prolonged respiratory allergy symptoms.
- On the flipside, a reduction in colder days could potentially lower a patient’s risk to upper respiratory infections.
- Changes in atmospheric circulation patterns may increase the occurrence of long-distance transport of pollen and pollutants.
- Increased air pollution and risk of wildfire smoke (CO₂) could lead to an aggravation of existing respiratory allergies.